The implication is moreso that these three faiths given, are suggestive to their members of following dogma blindly without critically thinking about the information they're fed, most often. There are exceptions of course, but of the religions out there, those are some of the worst for insistence upon following their rules to the letter regardless of how silly they sound, and to avoid thinking about it.
Faith can be a powerful tool if properly harnessed, and it can be a great thing to achieve. Blind faith, on the other hand, is a weapon against its' user. Pure belief in anything yeu're told without any comprehension behind it is not something we should really be striving for; that's whot makes flocks of mindless sheep that'll do anything they're told no matter how bad an idea it is, and is the origin of cults, rather than religions.
The thread was going to be more in depth asking about people's views on the concept of blind faith, whether they felt it was the only 'true' kind of faith, or if they preferred to temper their beliefs with knowledge and wisdom. I suppose the original joke, despite being a bad series of puns, was perhaps a bit too complex or misleading in nature though.
Anyways discuss stuffs XD